Flattened or Hierarchical Schematic Project?

Hello, I've been using Mentor's DC, DX and now xDx for the past 17 years. All my designs have been Hierarchical not Flattened. I wanted to ask the community which they prefer and also ask for their comments on the pros and cons of each. I like a Flattened designed because it the Cross Referencing is better; however, a Hierarchical design is better as showing connectivity between circuits.